Detection of surface defects in film-coated metals and measurement of coating thickness

Xiaoqing Yang; Junlong Chen; Yi Xie; Piqiang Su; Jiefang Luo; Xuexue Lei; Hui Xiao; Jianping Yuan; Zhanxia Zhu

doi:10.1063/1.5109480

Detection of surface defects in film-coated metals and measurement of coating thickness

Rev Sci Instrum. 2019 Sep;90(9):095005. doi: 10.1063/1.5109480.

Authors

Xiaoqing Yang¹, Junlong Chen¹, Yi Xie¹, Piqiang Su¹, Jiefang Luo¹, Xuexue Lei¹, Hui Xiao¹, Jianping Yuan², Zhanxia Zhu²

Affiliations

¹ College of Electronics and Information Engineering, Sichuan University, 610065 Chengdu, China.
² School of Astronautics, Northwestern Polytechnical University, 710129 Xian, China.

PMID: 31575246
DOI: 10.1063/1.5109480

Abstract

A novel sensor based on the interdigitated structure is presented to detect surface defects in film-coated metals and measure coating thickness. The detection and measurement are based on monitoring the shift of resonance frequency which is caused by the perturbation of electromagnetic field around the interdigitated structure. A 200-μm-wide defect was successfully detected in the experiment. In addition, the numerical simulations show that the designed sensor can detect a 50-μm-wide defect with a 220 MHz shift in the resonance frequency. The sensor is sensitive, inexpensive, portable, and can detect both defects and measure coating thickness.